1. Technical Field
The present invention relates to an inkjet recording apparatus and an inkjet recording method.
2. Related Art
Inkjet recording apparatus equipped with plural jetting heads that jet respectively different types of photocurable color inks onto conveyed paper sheets and an irradiation device that applies light to the photocurable color inks that have been jetted onto the paper sheets are known as image forming apparatus.
Here, Japanese Patent Application Laid-Open (JP-A) No. 2011-178142 discloses an inkjet recording apparatus which, when layer-jetting photocurable color inks onto paper sheets, jets the photocurable color inks in order beginning with the photocurable color ink whose photocurability is high for the purpose of countering bleeding.
Further, JP-A No. 2009-190394 and JP-A No. 2003-153888 disclose inkjet recording apparatus which, when layer-jetting color inks that are not photocurable onto paper sheets, jets the color inks in order beginning with the color ink whose concentration is large in order to control deterioration of granularity.
However, in JP-A No. 2011-178142, the irradiation device applies the light every time the photocurable color inks are jetted, but supposing a case where, considering energy efficiency, the irradiation device applies the light across the board after the inkjet recording apparatus has layer-jetted the photocurable color inks in order beginning with the photocurable color ink whose photocurability is high, the light would strike the layered ink (image membrane) in which the photocurable color inks are layered in descending order of photocurability in the thickness direction of the paper sheets. Here, descending order of photocurability is not always descending order of light blocking effect, so sometimes the ink layer having the large light blocking effect is positioned on the top layer side of the layered ink. When the ink layer having the large light blocking effect is positioned on the top layer side of the layered ink, the light becomes blocked at the top layer side of the layered ink and the amount of light passing through to the middle of the layered ink ends up decreasing. As a result, curing does not proceed to the middle of the layered ink, and the film strength of the layered ink ends up becoming lower.
Further, in JP-A No. 2009-190394 and JP-A No. 2003-153888, the inkjet recording apparatus layer jets color inks that are not photocurable, so depending on the passage of the light, the problem of the film strength of the layered ink becoming lower does not occur.